Immunohistochemical analysis of cyclooxygenase-2 induction during wound healing in dog skin

Cyclooxygenase (COX)-2 is an inducible isoform of COX and is expressed under abnormal health conditions. This study elucidated the cutaneous induction of COX-2 during the wound healing processes in dog skin. Dog skin was sutured after punch biopsy and investigated histologically and immunohistochemically on days 0 (normal), 1, 3, 5, 7, 10, and 14 after injury. Histological changes, including infiltration of inflammatory cells and proliferation of fibroblast-like cells, were observed as predicted, and there was a close and significant correlation between these 2 events. COX-2-positive cells were detected in the epidermis between days 1 and 7, and bimodal peaks were observed in the case of the percentage of COX-2-positive cells. In inflammatory cells, COX-positive signals were detected on day 3 only. Here, we clarified the localization and pattern of the induced COX-2 expression during wound healing in dog skin.